Process for the stabilization of metal organic compounds



Patented June 4, 1940 PAT PROCESS FOR THE STABILIZATION OF METAL ORGANIC COMPOUNDS Johannes Andreas van Melsen, Amsterdam,

Netherlands, assignor to Shell Development Company, San Francisco, Calif., a corporation of Delaware her 6, 1937 12 Claims.

This invention relates to the stabilization of heavy metal oxy and amino methylene ketones, and more particularly is concerned with the stabilization of the iron, cobalt, nickel and copper compounds of these ketones by the addition of relatively small amounts of aromatic amines.

Oxy and amino methylene ketones may be represented by the general formula in which R1 and R2 are hydrogen or organic radicals, such as alkyl, aryl or aralkyl radicals, and R3 is one of these organic radicals, whilst X is an OH, NHz or NHR4 group, in which R4 represents an organic radical, such as an alkyl, aryl or aralkyl group. The organic radicals may contain substituents, preferably neutral or basic reacting, which are normally capable of forming substantially stable compounds with hydrocarbons, such as halogen, CN, OH, OH,, COR, -NH2, NHR, NRz, SH, SR, -COOR, etc. Moreover, R2 and R3 together may form ring compounds.

Most of the copper and ferrous metal compounds of the above oxy and amino methylene ketones are at least partly soluble in hydrocarbon liquids and are useful as antiknock compounds for gasolines, as described in the copending application Serial No. 212,128, filed June 6, 1938, by Van Peski et a1.

It has been found that under many conditions these metal ketones or their solutions in hydrocarbon liquids tend to decompose slowly, not only when exposed to light, but also in the dark. Exposure to light normally accelerates their decomposition. I have discovered that this decomposition may be greatly retarded and often substantially completely inhibited by adding to the metal ketones described above certain primary and secondary aromatic amines. Suitable amines have the formula in which R1 is an aryl radical preferably phenyl or naphthylradical, which may be alkylated, and which may contain preferably not more than one substitution group that is incapable of reacting under normal storage conditions with which the metal ketones to be stabilized, such as an OH, NI-Iz, Cl, etc., group. Nitro, nitroso, acid groups, etc., attack the metal ketones and must therefore be avoided. Amines containing unsubstituted radicals are the most effective inhibitors, and the inhibiting powers of the amines in general decrease with the number and molecular size of the substituents. R2 of the amine may be an aryl radical of the same type as R1, or hydrogen,

' or a relatively small aliphatic or naphthenic radical having preferably not more than eighteen carbon atoms. Particularly effective amines are aniline and diphenyl amine. Other highly active amines are toluidine, methyl aniline, naphthyl amine. Somewhat less effective are for example the amino phenols, phenylene diamines, chloranilines, etc. The amounts of inhibitor required to effect stabilization are normally quite small, usually less than an equal weight of the metal ketone, although larger amounts may be used if desired. In many instances substantially complete stabilization was achieved with '5 to by weight of the inhibitor.

In addition to the inhibitors, other substances may be added such as mutual solvents or diluents. For example, a small amount of benzene frequently improves the homogeneity of non-homogeneous mixtures of the metal ketones and the herein described inhibitors, thereby improving the stabilizing effect of the inhibitor. If mutual solvents are required to improve homogeneity, I prefer to use amounts of the solvents at least sufficient to insure complete miscibility at about room temperature. The amounts of mutual solvents required to produce this result naturally will vary within extremely wide limits, i. e., from nothing or a bare trace to several times the volume of the mixture, and must be determined experimentally for different mixtures. Aside from benzene, other suitable mutual solvents are for instance lower alcohols, ethers, ketones, aliphatic amines, aromatic normally liquid hydrocarbons in general, etc. Furthermore metal ketones suit-- able as anti-knock agents may be dissolved in gasoline type fuels which themselves are substantially stable, such as straight-run, cracked or polymer gasolines, branched chain lower ethers. ketones, alcohols, etc., and solutions so produced may be stabilized by the addition of suitable amounts of my inhibitors. Thus antiknock fuels ready for use in spark ignition engines, or concentrates of such fuels to be used for blending, containing effective amounts of the metal-ketone antiknock agents may be produced, which are stable in storage for periods of many months, and which in the absence of the inhibitor might deteriorate.

While, in the foregoing, I have stressed in particular the stabilization of the ketone compounds of the ferrous metals and copper because of the importance of these compounds as antiknock agents in gasoline type fuels, it shall be understood that corresponding compounds of other heavy metals which are capable of uniting with A sample of 'the liquid copper compound of ethyl amino methylene acetone decomposed, when standing in semi-darkness for two weeks in a closed glass bottle, to the extent of settling out a small amount of a solid substance. Another sample of the same compound containing 10% by weight aniline, stored under identical conditions showed no signof decomposition after two months.

A third sample containing 10% by weight diphenyl amine also was completely undecomposed after two months standing under the above conditions.

Example II To the cobalt compound of ethyl amino methylene acetone an equal weight of aniline was added. The-mixture was exposed to light for 10 days and remained clear. In the absence of aniline the cobalt compound decomposed considerably under the above conditions. forming a precipitate.

I claim as my invention:

l. The process of stabilizing a compound selected from the class consisting of copper and ferrous compounds of oxy and of amino methylene ketones comprising adding to said compound an aromatic amine in which R1 is phenyl and R2 is a radical selected from the group consisting of hydrogen and phenyl.

2. The process of stabilizing a compound selected from the class consisting of copper and ferrous compounds of oxy and of amino methylcne ketones, comprising adding to said compound an aromatic amine HN R1 Bil in which R1 is phenyl and R: is a radical selected from the group consisting of hydrogen and phenyl, and further adding an amount of a mutual solvent for said compound, said amount being-sufficient to produce a homogeneous mixture.

3. A composition of matter comprising a compound selected from the class consisting of copper and ferrous compounds of oxy and of amino methylene ketones, in admixture with an arcmatic amine in which R1 is phenyl and R2 is a radical selected from the group consisting of hydrogen and phenyl.

4. The composition of claim 3 containing an amine, in which at least one of the radicals R1 and R2 is an unsubstituted aryl radical.

5. The composition of claim 3 containing an amine, in which at least one of the radicals R1 and R2 is a phenyl radical.

6. The composition of claim 3 in which the amine is aniline.

7. The composition of claim 3 in which the amine is diphenyl amine.

8. The composition of claim 3 in which the amount of the amine is from 5 to 100% by weight of the metal compound.

9. A composition of matter comprising a compound selected from the class consisting of copper and ferrous compounds of oxy and of amino methylene ketones, in admixture with an aromatic amine in which R1 is phenyl and R2 is a radical selected from the group consisting of hydrogen and phenyl, and with a mutual solvent for said compound and amine.

10. A homogeneous composition of matter comprising a compound selected from the class consisting of copper and ferrous compounds of oxy and of amino methylene ketones, in admixture with an aromatic amine in which R; is phenyl and R2 is a radical selected in which R1 is phenyl and R2 is a radical selected from the group consisting of hydrogen and phenyl.

12. A homogeneous composition of matter comprising a compound selected from the class con-- sisting of copper and ferrous compounds of oxy and of amino methylene ketones, in admixture with an aromatic amine HN Ri of which R1 is phenyl and R: is a radical selected from the group consisting of hydrogen and phenyl and with a mutual solvent for said compound and amine in "an'amount at least sufficient to insure complete miscibility of .the components at normal room temperature, the amount of said amine being from 5 to 100% by weight of the metal compound.

JOHANNES ANDREASVAN 

